JP2003203214A - Noncontact type ic card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the influence on communication when overlapping two or more noncontact type IC cards. <P>SOLUTION: In this noncontact type IC card, a data communication is performed in a noncontact state by a capacitor formed of electrodes 17 and 19 connected to both ends of an antenna coil 14 fixed to the peripheral part of an insulating substrate 11 and the insulating substrate 11; and an integrated circuit 15 having a transmitting and receiving part for performing an arithmetic processing of a received signal by the power generated on the basis of a received signal radio wave and returning the operation result to the outside, a part of the transmitting and receiving part being connected to both the ends of the antenna coil 14. The capacitor formed of the electrodes 17 and 19 and the insulating substrate 11 is arranged on the outside of the antenna coil 14. According to such a structure, since the conductive electrodes 17 and 19 forming a part of the structure of the capacitor are never arranged on the inside of the antenna coil 14 even if two or more noncontact type IC cards are overlapped, satisfactory data communication can be realized. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type IC which enables data communication with the outside in a non-contact state.
The present invention relates to a card, and more particularly to an improvement in the arrangement of capacitors that are formed by using a wiring pattern.

[0002]

2. Description of the Related Art A non-contact type IC card is a non-contact type IC card which has a transmission frequency from a radio transceiver called a reader / writer.
Data communication is performed by an integrated circuit that is configured in at least a transmission / reception unit and a tuning unit mounted in the card.

Generally, a tuning capacitor is formed by connecting a chip capacitor by soldering or by using an insulating substrate itself as a dielectric and sandwiching its front and back with conductive patterns.

As shown in FIG. 5, in a conventional non-contact type IC card, a pattern antenna coil 52 serving as an antenna is arranged near the outer shape of the IC card 51, and a pattern capacitor 53 is arranged inside the antenna coil 52. There is. In this case, since the pattern capacitor 53 located in the position surrounded by the antenna coil 52 is a conductor, it serves as a shield plate for a magnetic field generated in the antenna coil 52 during communication. In particular, when a plurality of IC cards shown in FIG. 5 in which the capacitor pattern is arranged inside the antenna coil 52 are stacked, the area of the shielding plate becomes relatively large as shown in FIG. I was letting it.

The arrangement of a capacitor outside the antenna coil is disclosed in Japanese Patent Laid-Open No. 2000-123136. In this structure, an antenna coil is mounted on an approximately half area of the circuit board, and a capacitor chip component for tuning is mounted on the circuit board of the remaining area outside the antenna coil.

In this case, when one of the two IC cards is stacked upside down, not only the capacitor chip component is located inside the antenna coil but the communication function is deteriorated, and an expensive capacitor chip is used. There is a problem such as doing.

[0007]

As described above, in the conventional non-contact type IC card, the pattern forming the electrode of the capacitor is a conductor and therefore becomes a shield plate during communication. In particular, when a plurality of cards in which the electrodes of the capacitors are arranged inside the antenna coil are stacked, the area of the shield plate becomes relatively large, and the communication function is significantly deteriorated.

Therefore, an object of the present invention is a non-contact type IC.
An object of the present invention is to provide a non-contact type IC card that reduces adverse effects on communication not only when using one card but also when stacking a plurality of cards.

[0009]

In order to solve the above-mentioned problems, the present invention provides a non-contact type IC card of the present invention, wherein an insulating substrate and an antenna coil fixed to the outer peripheral portion of the insulating substrate are received. The reception signal is arithmetically processed with electric power generated based on the signal radio wave, and a transmission / reception unit for returning the calculation result to the outside is provided, and the transmission / reception unit is partially connected to both ends of the antenna coil. A first integrated circuit, which is fixed to the outside of the antenna coil of the insulating substrate and is connected to one end of the antenna coil.
Electrode and a second electrode that is disposed so as to face the first electrode with the insulating substrate sandwiched therebetween, is fixed to the insulating substrate, and is connected to the other end of the antenna coil. To do.

According to the above means, the electrode of the capacitor formed at the same time when the wiring pattern is formed in the antenna coil is not arranged, so that the deterioration of the data communication function can be prevented.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a configuration diagram for explaining an embodiment of the present invention. First, in FIG. 1A, 11 is an insulating substrate formed using polyethylene terephthalate having a thickness of about 0.05 mm, for example. An aluminum foil having a thickness of about 0.02 mm is fixed on the insulating substrate 11, and the aluminum foil is etched to form the wiring pattern 12. The outer shape of the insulating substrate 11 is slightly smaller than that of the card casing 13 having a width of 85 mm and a length of 54 mm.

A wiring pattern 12 is further formed on the insulating substrate 11.
The antenna coil 14 is formed by etching at the same time as the formation of. The outer periphery of the antenna coil 14 and the insulating substrate 11
The distances 11a to 11d from the upper, lower, left, and right edges are about 4 mm, respectively. The antenna coil 14 is wound around the outer peripheral portion of the insulating substrate 11 once or more, for example, 3 or 4 times. Both terminals 14a and 14b of the antenna coil 14 are connected to an integrated circuit 15 mounted on the insulating substrate 11 by a flip chip method, for example.

The integrated circuit 15 receives a signal radio wave from the outside through the antenna coil 14, generates electric power based on the received radio wave, performs arithmetic processing, and calculates the result obtained by the arithmetic processing. It has a function to send back to the outside with the surplus power used in.

On the surface of the insulating substrate 11, one electrode 17 constituting a capacitor is formed by etching at the same time as the formation of the wiring pattern 12 at a position between the antenna coil 14 and the side edge 111 of the insulating substrate 11. To do. Electrode 1
7 has a plurality of narrow pattern cut portions 18a, 18
b to 18n are formed.

At the opposite position of the electrode 17 on the surface of the insulating substrate 11, the other electrode 19 constituting a capacitor is formed as shown in FIG. 1 (b). The electrodes 17 and 19 are
A capacitor is formed by using the insulating substrate 11 as a dielectric. Similarly to the electrode 17, narrow pattern cut portions 20a, 20b to 20n are formed on the electrode 19.

The electrode 17 is taken out from the wiring pattern 12 and the electrode 19 is taken out from the wiring pattern 121 to the surface of the insulating substrate 11 via a through hole (not shown) and the integrated circuit 15 is obtained.
Connect to each. As a result, the resonance circuit 21 is formed between the antenna coil 14 and the antenna coil 14, as shown in FIG. The resonance circuit 21 is adjusted by the pattern cut portion 1 of the electrode 17.
Adjustment can be achieved by trimming 7a and 17b to 17n so as to obtain a desired tuning frequency.

In this way, it is possible to realize a non-contact type IC card which enables data communication with the outside in a non-contact state. In this embodiment, a plurality of non-contact type I
When the C cards are used in an overlapping manner, the pattern capacitor is not in a position that affects the magnetic field of the antenna, so that reliable data transmission / reception can be realized. Further, since the capacitors can be formed at the same time as the process of forming the wiring pattern, it is not necessary to attach new parts and the like, which contributes to cost reduction.

In this embodiment, the thickness is 0.05 m.
m polyethylene terephthalate as a dielectric,
When sandwiched between the front and back aluminum electrodes, the electrode area is 4 mm x 1
The capacity was about 10 PF at 0 mm.

FIG. 3 is a block diagram for explaining another embodiment of the present invention. In this embodiment, it is formed at a position between the side edge 112 of the insulating substrate 11 on the upper side in the drawing. One electrode 31 is formed.

That is, the electrode 31 is formed on the upper surface in the figure, and an electrode (not shown) is formed on the surface facing the back surface of the electrode 31 to form a capacitor here. Both ends of this capacitor are also connected to desired terminals of the integrated circuit 15.

In this case, since the capacitors are formed symmetrically above and below the insulating substrate 11, even if a plurality of non-contact type IC cards configured as shown in FIG. Can be eliminated as much as possible. Therefore, the inhibition of the magnetic field in the antenna coil can be suppressed, and reliable data communication can be performed.

FIG. 4 is an explanatory view showing in perspective from the front a state in which the four non-contact type IC cards constructed in FIG. 3 are superposed in four ways. The figure shows that no matter how many layers are stacked, the electrodes that constitute the capacitor are not placed inside the antenna coil 14, which affects the data transmission. It is possible to satisfactorily send and receive IC card data. Note that this point is the same as in the non-contact type IC card of FIG.

The present invention is not limited to the above-described embodiment, and for example, it is not always necessary to form the pattern cut portions 19a, 19b to 19n in the electrode of FIG. Further, although the capacitor is supposed to be arranged on either the upper side or the lower side of the insulating substrate 11 in the figure, the antenna coil 1
It may be arranged on either the left side or the right side in the figure outside of 4. Although the mounting portion of the integrated circuit 15 is arranged inside the antenna coil 14, the communication function is further improved by arranging the mounting portion outside the antenna coil 14 like the pattern capacitor.

Although the specific dimensions have been described in the description of FIG. 1, the dimensions shown are merely examples, and the dimensions are not limited to these as long as the dimensions do not depart from the gist of the present invention. Furthermore, the integrated circuit 15 may be mounted by a wire bonding method, and the electrodes on the front and back sides are made of aluminum of the same type, but a combination of copper foil and aluminum foil may be used. Furthermore, by disposing another antenna coil inside the antenna coil 14 and using it together with the antenna coil 14, the communication characteristics can be improved by the action of the antenna inside when the cards are stacked. .

[0025]

As described above, according to the non-contact type IC card of the present invention, good data communication can be performed even in a situation where a plurality of non-contact type IC cards are used in a stacked manner.

[Brief description of drawings]

FIG. 1 is a front view for explaining a first embodiment of the present invention.

FIG. 2 is an equivalent circuit of a main part of FIG.

FIG. 3 is a front view for explaining a second embodiment of the present invention.

FIG. 4 is a front view for explaining an effect when a plurality of non-contact IC cards shown in FIG. 3 are used in an overlapping manner.

FIG. 5 is a front view for explaining a conventional non-contact type IC card.

FIG. 6 is a front view for explaining a problem that occurs when the non-contact IC cards of FIG. 5 are used in an overlapping manner.

[Explanation of symbols]

11 ... Insulating substrate 12 ... Wiring pattern 13 ... Card exterior 14 ... Antenna coil 15 ... Integrated circuits 17, 19, 31 ... Electrodes 18a, 18b-18n, 20a, 20b-20n ... Pattern cut portions 111, 112 ... Side edges

Claims (4)

[Claims] 1. An insulating substrate, an antenna coil fixed to an outer peripheral portion of the insulating substrate, and an arithmetic processing of a received signal with electric power generated based on a received signal radio wave, and returning the arithmetic result to the outside. And an integrated circuit in which a part of the transmitting / receiving section is connected to both ends of the antenna coil, and is fixed to the outside of the antenna coil of the insulating substrate and connected to one end of the antenna coil. A first electrode; and a second electrode that is arranged to face the first electrode with the insulating substrate sandwiched therebetween and is fixed to the insulating substrate and connected to the other end of the antenna coil. Non-contact type IC card characterized by. 2. The non-contact type IC card according to claim 1,
A non-contact type IC card, wherein the capacitors are arranged so that the capacitors are substantially overlapped when a plurality of them are stacked. 3. The non-contact type IC card according to claim 1, wherein the antenna coil is formed on the insulating substrate by etching at the same time when a wiring pattern is formed by etching. 4. The non-contact type IC card according to claim 1, wherein the first and second electrodes form a capacitor having the insulating substrate as a dielectric.